That has been a hallmark of Ang Lee's movies since his first Taiwanese productions, and it has only become clearer in his American work. Connecticut suburbanites, 19th-century aristocrats, New West cowboys -- they all struggle mightily to contain their secret urges. Until one day, fatefully -- perhaps fatally -- they can't.

That theme, which you can find in Lee movies as diverse as "Hulk" and "Lust, Caution," reaches a generational climax in "Taking Woodstock," a film about the staging of the epochal 1969 concert. It's a conflict between old and new, straight-laced and wide-open -- and, unfortunately, between Lee and his collaborators.

Lee's directorial work here is, typically, excellent. In scenes of the promoters setting up the stage (and the "freaks" descending on the tiny Catskills town), he uses the same split screens and overlapping editing that Michael Wadleigh made famous in his original concert film; in the (almost obligatory) acid-trip sequence, the colors swirl like melting paintings.

But Lee is let down on other fronts.

James Schamus has written many of Lee's scripts (although not for two of his best films, "Brokeback Mountain" and "Sense and Sensibility"), and the two clearly understand each other's strengths. Yet too much of "Taking Woodstock" seems barely sketched out.

Of course, the story itself takes place, deliberately, on the edges of history. It details the true story of how a shy kid with a failing motel (Elliot Tiber, on whose memoir the film is based) helped broker the deal that brought "3 Days of Peace and Music" to a nearby dairy farm (and utter chaos to much of upstate New York).

The movie is, thus, about Eliot's personal revolution, not the one happening onstage; there are no lookalikes lip-synching to Janis and Jimi, no restagings of sets by Santana or the Airplane. Like most of the people who attended, the best we get are snatches of music in the distance.

Yet for a movie based on a real person's memoir, very little in "Taking Woodstock" feels singular or even real. A self-medicating veteran who keeps having flashbacks is identical to ones we've seen in so many other movies; a motherly-but-macho drag queen seems to have wandered in from "The World According to Garp."

Even our hero isn't much of a presence; he's more of a nebbish with a crudely domineering mother. Eliot needs some spark of personality, but Demetri Martin, a hot alternative comic who unwisely let someone convince him he was an actor, too, can't provide it. He's got a bad case of the mopes, and it's catching.

The rest of the performances are all over the place. Jonathan Groff, a stage actor from "Spring Awakening" and the recent "Hair" revival, makes a terrific movie debut as festival organizer Michael Lang; he's got the real Lang's elfin but ultimately unreadable smile down pat. But as Elliot's mother, the usually immaculate Imelda Staunton all but attacks the scenery with a knife and fork.

There are some amusements along the way, including a terrible (and frequently nude) avant-garde theater troupe, and Liev Schreiber as a Marine in a housedress. There's also some forced, nudge-nudge foreshadowing, as when Lang talks about that upcoming Stones concert he's involved with. You know, Altamont.

Whoa. Bummer.

But even coupled with Lee's careful filmmaking, that's not enough for two hours of movie -- or even a fresh, sideways look at a famous event. For that, you might want to search out another Schreiber film about that subject, the adultery drama "A Walk on the Moon."

Or even -- here's a novel idea -- the original crunchy-granola documentary itself.

Stephen Whitty may be reached at swhitty@starledger.com or (212) 790-4435.